CODEWITHSUNDEEP
python
Phong
Phong

Reputation: 6768

How to return all possible combination

I have multiple array like following

A[0] = [a1, a2, a3]
A[1] = [b1, b2]
...
A[k-1] = [k1, ...]

I would like to generate all the vector [a?, b?, ..., k?] possible I looked at itertool library, but it does not feet my need.

How can I simply do it. (I though about recursion but I guess there is a more simpler solution).

Upvotes: 0

Views: 51

Answers (1)

Martijn Pieters
Martijn Pieters

Reputation: 1121834

You'd use itertools.product():

from itertools import product


for vector in product(*A):
    # vector is [a[0], b[0], ..., k[0]] through to [a[k-1], [b[k-1], ..., k[k-1]]
    # odometer style

Demo:

>>> from itertools import product
>>> A = [[1, 2, 3], ['foo', 'bar'], ['spam', 'eggs']]
>>> for vector in product(*A):
...     print vector
... 
(1, 'foo', 'spam')
(1, 'foo', 'eggs')
(1, 'bar', 'spam')
(1, 'bar', 'eggs')
(2, 'foo', 'spam')
(2, 'foo', 'eggs')
(2, 'bar', 'spam')
(2, 'bar', 'eggs')
(3, 'foo', 'spam')
(3, 'foo', 'eggs')
(3, 'bar', 'spam')
(3, 'bar', 'eggs')

Upvotes: 4

Related Questions